As the trial begins of Lewis 'Scooter' Libby, former chief of staff to Dick Cheney, on charges of lying about the disclosure of a CIA officer's identity begins, we profile key figures in the case.
LEWIS 'SCOOTER' LIBBY
Lewis 'Scooter' Libby is Dick Cheney's chief aide
Mr Libby has been indicted by the grand jury on five counts including obstruction of justice, perjury and providing false statements.
As chief aide to Vice-President Dick Cheney, he has been involved in almost every major decision made by the Bush administration.
Mr Libby has admitted that he discussed Ms Plame with at least two reporters, but he testified that he had never mentioned her name or her covert status at the CIA.
The former official said he had made a "mistake"
In September 2006, US former Deputy Secretary of State Richard Armitage admitted that it was he who had first disclosed that Valerie Plame was an undercover CIA agent.
Mr Armitage said his revelation to two journalists - one of whom was Washington Post reporter Bob Woodward - had been "a terrible mistake", one which he had made inadvertently, thinking Ms Plame's job was not secret.
The former official, who left the administration at the end of Mr Bush's first term, along with his boss, former secretary of state Colin Powell, apologised for the revelation made in conversation with the journalists in 2003.
His admission scotched suggestions that the leak had originated at the White House as retribution for comments made by Ms Plame's husband, former ambassador Joseph Wilson, about the Iraq war.
Former Ambassador Joseph Wilson criticised the Bush administration
In 2003 the former US ambassador wrote an opinion piece for the New York Times in which he accused President George W Bush's administration of twisting intelligence on Iraq.
Mr Wilson said he had travelled to Niger to investigate a claim that Iraq had tried to buy nuclear material there, but found no evidence to prove it.
President Bush used the Niger claim as part of the justification for the 2003 invasion of Iraq.
Mr Wilson alleges that his wife Valerie's name was deliberately leaked as the instigator of his Niger trip in an attempt to undermine him.
Valerie Plame (left) posed with her husband for the cover of Vanity Fair
Valerie Plame Wilson is a former CIA officer married to former US Ambassador Joseph Wilson.
The revelation of her identity as a serving agent in 2003 is the basis for the Plame affair, or CIA leak scandal.
She was first named publicly by journalist Robert Novak in a July 2003 newspaper column that cited "administration officials".
Some argue the revelation was made by the Bush administration to get back at her husband after he criticised the administration for twisting intelligence on Iraq.
Patrick Fitzgerald was appointed to see if a crime had been committed
Mr Fitzgerald - a zealous and dogged Chicago prosecutor - was appointed, on 30 December 2003, as special counsel to head up the inquiry into the leaking of Valerie Plame's name.
During his investigation the 44-year-old US attorney for the Northern District of Illinois has personally interviewed numerous officials from the CIA, White House and State Department.
Journalist Robert Novak first publicly revealed that Ms Plame was a covert CIA agent in his newspaper column in July 2003 - citing two administration officials - and saying that Mr Wilson's Niger trip was inspired by Ms Plame.
While Mr Novak is believed to have co-operated with the Fitzgerald inquiry, he has declined to comment.
The journalist, seen as a political conservative, has been no stranger to controversy in a long career as a political commentator.
He was once suspended by CNN in August 2005 after he cursed and walked off the set of Inside Politics when a fellow pundit needled him.
Mr Cooper wrote an article that said Mr Wilson's wife was a CIA agent
Time magazine reporter Matthew Cooper wrote an article following the Novak column in July 2003 for Time's website, saying that "some government officials" had provided him with information similar to Mr Novak's.
Mr Cooper agreed to testify to the grand jury investigation in July this year when he faced the prospect of jail for contempt of court.
He said that it was through a conversation with Bush aide Karl Rove that he learned for the first time that Mr Wilson's wife worked at the CIA but said that Mr Rove did not name Valerie Plame or tell him she was a covert agent.
Mr Cooper also wrote in Time that he discussed Mr Wilson and his wife with Lewis "Scooter" Libby, the vice-president's chief of staff.
Judith Miller was jailed for refusing to reveal her source
Judith Miller of the New York Times, a Pulitzer Prize-winning reporter, had done research into matters related to the Plame case but never actually published anything.
However, she came to the attention of the prosecutor because of her inquiries and ended up spending 85 days in jail after she refused to name her White House source.
She was released from jail in September 2005 and agreed to testify only after formal authorisation from her source.
Miller says she spoke to Dick Cheney's chief aide Lewis "Scooter" Libby but that he did not name Ms Plame.
Mr Rove (right) is President Bush's chief political strategist
President George W Bush's senior adviser and chief political strategist denies the accusation that he revealed the identity of Ms Plame to Time magazine reporter Matthew Cooper in retaliation for her husband's criticisms of the administration.
Mr Rove has testified four times to the grand jury investigating the leak.
Some consider him the power behind the throne of the Bush presidency.
Investigator Patrick Fitzgerald said in 2006 that the aide would not face charges over the leaking of Ms Plame's identity.